Widespread proliferation of mobile battery-powered hand-held devices with audio-visual capture and communication capability, have prompted research in real-time encoding and communication algorithms that are low-complexity. The primary channel for communication is unreliable wireless, making the problem of reliable communication even more challenging. Also, for many low-power devices, encoding a captured video at full-resolution can be an excessive drain on power.
Most prior solutions do not address good compression performance, error resilience, and low-encoding complexity simultaneously, even though most handheld devices need to address all. Naïve solutions such as all Intra encoding or encoding with frame difference are low-complexity, but not efficient enough in bit-rate. Recently, a variety of solutions have been proposed for reversed complexity encoding that try to push complex motion estimation tasks to the decoder side in order to control encoding complexity, while still allowing a compact bit-stream to be transmitted. Some of these solutions use some form of Wyner-Ziv coding. While use of feedback has been used extensively in the context of Wyner-Ziv coding, such feedback has mostly been based on channel coding mechanisms for Wyner-Ziv coding, which are not the most efficient, and inevitably require multiple back and forth transmissions that increase the delay excessively.
Moreover, most other work on reversed complexity coding use temporal interleaving. This requires frame interpolation techniques at the receiver end to generate the side-information. However, the quality of the side-information generated by that manner usually is low and has many artifacts.
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